Field of the Invention
The present invention relates to a fluid pressure cylinder which causes a piston to be displaced along axial directions under the action of a pressure fluid.
Description of the Related Art
Heretofore, a fluid pressure cylinder has been used as a means for driving various types of industrial machines such as workpiece transport and positioning devices or the like.
Generally, a fluid pressure cylinder causes a piston, which is disposed in the interior of a cylinder main body, to be displaced along axial directions through the action of a pressure fluid that is supplied from a pressure fluid port, whereby transport, positioning, or the like of workpieces is carried out through a piston rod connected to one end side of the piston.
In relation to this type of cylinder, recently, there has been a demand to minimize the scale of the fluid pressure cylinder, and in particular, to shorten the length (total length of the fluid pressure cylinder) in the axial direction, under a condition in which the stroke length of the piston (piston rod) is maintained.
Responsive to such demands in the art, the present applicant has proposed a fluid pressure cylinder in which the total length thereof is shortened while maintaining the stroke length of the fluid pressure cylinder, by blocking an opening of the cylinder main body with a substantially planar cap, and abutting the piston against the cap when the piston reaches a displacement terminal end position (see Japanese Laid-Open Patent Publication No. 2005-240936).
As shown in FIG. 11, in such a fluid pressure cylinder, a stepped portion 3 is provided by carrying out a step-forming process on an end surface of the piston 2 that confronts the cap 1. Owing thereto, when the piston 2 comes into abutment against the cap 1, a space (air passage) S2 is formed through which the pressure fluid can be introduced between the cap 1 and the piston 2.